Despite the fact the presumptive GOP nominee has obliterated his challengers during a raucous primary season, garnered a handful of endorsements from Washington, and enjoys the enthusiastic support of millions of voters, portions of the donor class are not sold.

But, according to a report from The New York Times, a handful of deep-pocketed donors have suggested that they will ignore Trump's calls. Among them, New York investor Paul Singer, "who has spent at least $28 million for national Republicans since the 2012 election," The Times noted.